kernel/linux.git/tools/perf/util/Build, branch v6.12.80

perf report: Support LLVM for addr2line()

2024-09-03T13:15:16+00:00

In addition to the existing support for libbfd and calling out to an external addr2line command, add support for using libllvm directly. This is both faster than libbfd, and can be enabled in distro builds (the LLVM license has an explicit provision for GPLv2 compatibility). Thus, it is set as the primary choice if available. As an example, running 'perf report' on a medium-size profile with DWARF-based backtraces took 58 seconds with LLVM, 78 seconds with libbfd, 153 seconds with external llvm-addr2line, and I got tired and aborted the test after waiting for 55 minutes with external bfd addr2line (which is the default for perf as compiled by distributions today). Evidently, for this case, the bfd addr2line process needs 18 seconds (on a 5.2 GHz Zen 3) to load the .debug ELF in question, hits the 1-second timeout and gets killed during initialization, getting restarted anew every time. Having an in-process addr2line makes this much more robust. As future extensions, libllvm can be used in many other places where we currently use libbfd or other libraries: - Symbol enumeration (in particular, for PE binaries). - Demangling (including non-Itanium demangling, e.g. Microsoft or Rust). - Disassembling (perf annotate). However, these are much less pressing; most people don't profile PE binaries, and perf has non-bfd paths for ELF. The same with demangling; the default _cxa_demangle path works fine for most users, and while bfd objdump can be slow on large binaries, it is possible to use --objdump=llvm-objdump to get the speed benefits. (It appears LLVM-based demangling is very simple, should we want that.) Tested with LLVM 14, 15, 16, 18 and 19. For some reason, LLVM 12 was not correctly detected using feature_check, and thus was not tested. Committer notes: Added the name and a __maybe_unused to address: 1 13.50 almalinux:8 : FAIL gcc version 8.5.0 20210514 (Red Hat 8.5.0-22) (GCC) util/srcline.c: In function 'dso__free_a2l': util/srcline.c:184:20: error: parameter name omitted void dso__free_a2l(struct dso *) ^~~~~~~~~~~~ make[3]: *** [/git/perf-6.11.0-rc3/tools/build/Makefile.build:158: util] Error 2 Signed-off-by: Steinar H. Gunderson Tested-by: Arnaldo Carvalho de Melo Cc: Ian Rogers Link: https://lore.kernel.org/r/20240803152008.2818485-1-sesse@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf bpf-filter: Add build dependency to header files

2024-08-28T21:21:24+00:00

The flex and bison files need to be recompiled when one of these header filters are changed. * util/bpf-filter.h * util/bpf_skel/sample-filter.h Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240826221045.1202305-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf cap: Tidy up and improve capability testing

2024-08-20T20:53:12+00:00

Remove dependence on libcap. libcap is only used to query whether a capability is supported, which is just 1 capget system call. If the capget system call fails, fall back on root permission checking. Previously if libcap fails then the permission is assumed not present which may be pessimistic/wrong. Add a used_root out argument to perf_cap__capable to say whether the fall back root check was used. This allows the correct error message, "root" vs "users with the CAP_PERFMON or CAP_SYS_ADMIN capability", to be selected. Tidy uses of perf_cap__capable so that tests aren't repeated if capget isn't supported. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Changbin Du Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Oliver Upton Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240806220614.831914-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fork and launch 'perf record' when 'perf stat' needs to get retire latency value for a metric.

2024-08-13T18:24:48+00:00

When retire_latency value is used in a metric formula, evsel would fork a 'perf record' process with "-e" and "-W" options. 'perf record' will collect required retire_latency values in parallel while 'perf stat' is collecting counting values. At the point of time that 'perf stat' stops counting, evsel would stop 'perf record' by sending sigterm signal to 'perf record' process. Sampled data will be processed to get retire latency value. Another thread is required to synchronize between 'perf stat' and 'perf record' when we pass data through pipe. Retire_latency evsel is not opened for 'perf stat' so that there is no counter wasted on it. This commit includes code suggested by Namhyung to adjust reading size for groups that include retire_latency evsels. In current :R parsing implementation, the parser would recognize events with retire_latency modifier and insert them into the evlist like a normal event. Ideally, we need to avoid counting these events. In this commit, at the time when a retire_latency evsel is read, set the retire latency value processed from the sampled data to count value. This sampled retire latency value will be used for metric calculation and final event count print out. No special metric calculation and event print out code required for retire_latency events. Reviewed-by: Namhyung Kim Signed-off-by: Weilin Wang Acked-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Caleb Biggers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Perry Taylor Cc: Peter Zijlstra Cc: Samantha Alt Link: https://lore.kernel.org/r/20240720062102.444578-4-weilin.wang@intel.com [ Squashed the 3rd and 4th commit in the series to keep it building patch by patch ] [ Constified the 'struct perf_tool' pointer in process_sample_event() ] [ Use perf_tool__init(&tool, false) to address a segfault I reported and Ian/Weilin diagnosed ] Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Move fill defaults into tool.c

2024-08-12T21:05:39+00:00

The aim here is to eventually make perf_tool__fill_defaults() an init function so that the tools struct is more const. Create a tool.c to go along with tool.h. Move perf_tool__fill_defaults() out of session.c into tool.c along with the default stub values. Add perf_tool__compressed_is_stub() for a test in perf_session__process_user_event(). perf_session__process_compressed_event() is only used from being default initialized so migrate into tool.c. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Anshuman Khandual Cc: Athira Rajeev Cc: Huacai Chen Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Cameron Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Nick Terrell Cc: Oliver Upton Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Suzuki Poulouse Cc: Will Deacon Cc: Yanteng Si Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20240812204720.631678-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Move BPF disassembly routines to separate file to avoid clash with capstone bpf headers

2024-08-01T21:54:19+00:00

There is a clash of the libbpf and capstone libraries, that ends up with: In file included from /usr/include/capstone/capstone.h:325, from util/disasm.c:1513: /usr/include/capstone/bpf.h:94:14: error: ‘bpf_insn’ defined as wrong kind of tag 94 | typedef enum bpf_insn { So far we're just trying to avoid this by not having both headers included in the same .c or .h file, do it one more time by moving the BPF diassembly routines from util/disasm.c to util/disasm_bpf.c. This is only being hit when building with BUILD_NONDISTRO=1, i.e. building with binutils-devel, that isn't the in the default build due to a licencing clash. We need to reimplement what is now isolated in util/disasm_bpf.c using some other library to have BPF annotation feature that now only is available with BUILD_NONDISTRO=1. Fixes: 6d17edc113de1e21 ("perf annotate: Use libcapstone to disassemble") Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/lkml/ZqpUSKPxMwaQKORr@x1 Signed-off-by: Arnaldo Carvalho de Melo

perf util: Make util its own library

2024-06-26T18:07:42+00:00

Make the util directory into its own library. This is done to avoid compiling code twice, once for the perf tool and once for the perf python module. For convenience: arch/common.c scripts/perl/Perf-Trace-Util/Context.c scripts/python/Perf-Trace-Util/Context.c are made part of this library. Signed-off-by: Ian Rogers Reviewed-by: James Clark Cc: Suzuki K Poulose Cc: Kees Cook Cc: Palmer Dabbelt Cc: Albert Ou Cc: Nick Terrell Cc: Gary Guo Cc: Alex Gaynor Cc: Boqun Feng Cc: Wedson Almeida Filho Cc: Ze Gao Cc: Alice Ryhl Cc: Andrei Vagin Cc: Yicong Yang Cc: Jonathan Cameron Cc: Guo Ren Cc: Miguel Ojeda Cc: Will Deacon Cc: Mike Leach Cc: Leo Yan Cc: Oliver Upton Cc: John Garry Cc: Benno Lossin Cc: Björn Roy Baron Cc: Andreas Hindborg Cc: Paul Walmsley Signed-off-by: Namhyung Kim Link: https://lore.kernel.org/r/20240625214117.953777-7-irogers@google.com

perf mem-info: Move mem-info out of mem-events and symbol

2024-05-07T21:06:44+00:00

Move mem-info to its own header rather than having it split between mem-events and symbol. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Ben Gainey Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: K Prateek Nayak Cc: Kajol Jain Cc: Kan Liang Cc: Li Dong Cc: Mark Rutland Cc: Namhyung Kim Cc: Oliver Upton Cc: Paran Lee Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sun Haiyong Cc: Tim Chen Cc: Yanteng Si Cc: Yicong Yang Link: https://lore.kernel.org/r/20240507183545.1236093-7-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf util: Add shellcheck to generate-cmdlist.sh

2024-04-12T20:54:02+00:00

Add shellcheck to generate-cmdlist.sh to avoid basic shell script mistakes. Reviewed-by: James Clark Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kajol Jain Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Oliver Upton Cc: Peter Zijlstra Cc: Ravi Bangoria Link: https://lore.kernel.org/r/20240409023216.2342032-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Split out util/disasm.c

2024-04-03T14:48:57+00:00

The util/annotate.c code has both disassembly and sample annotation related codes. Factor out the disasm part so that it can be handled more easily. No functional changes intended. Committer notes: Add missing include env.h, util.h, bpf-event.h and bpf-util.h to disasm.c, to fix things like: util/disasm.c: In function ‘symbol__disassemble_bpf’: util/disasm.c:1203:9: error: implicit declaration of function ‘perf_exe’ [-Werror=implicit-function-declaration] 1203 | perf_exe(tpath, sizeof(tpath)); | ^~~~~~~~ Signed-off-by: Namhyung Kim Tested-by: Ian Rogers Cc: Adrian Hunter Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240329215812.537846-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo